The European Patent Office (EPO) has revoked a patent owned by global agricultural giant Monsanto for the genetic modification
(GM) of soybeans, saying the technique it approved 13 years ago lacked "novelty".

The technique, which describes a way of creating any kind of GM soybean without reference to the specific genes being introduced,
has helped make Monsanto the dominant force in GM soybeans — the company owns nearly 90% of the global market. Opponents complained
that the patent gave Monsanto de facto control over all GM soybeans, and have been fighting against it since it was granted
in 1994.

At a hearing on 3 May, the EPO revoked the patent. The board's decision is final, says Rainer Osterwalder, spokesman for the
EPO, with no further appeals available.

The decision will no doubt have an impact on other GM technology patents, Osterwalder told Nature. "Case law is important,"
he says.

But the patent was due to expire in 2008 anyway. A spokesperson for Monsanto says: "We do not expect this decision to have
an impact on Monsanto's business." The EPO will not issue a detailed written explanation of the legal basis of its decision
for three to six months, Osterwalder says.

Firing line

The application for the soybean patent was first submitted in 1988 by US biotech company Agracetus under the title 'Particle-mediated
transformation of soybean plants and lines'.

The technique, dubbed a 'particle gun', involves introducing foreign genes into regenerable soybean tissues by coating on
carrier particles, which are physically accelerated into plant tissues. The tissues are then recovered and regenerated into
whole sexually mature plants. The progeny are recovered from seed set by these plants; a portion will contain in their genome
the foreign gene.

This idea was actively researched by several teams during the 1980s, one of which was the team at Agracetus, according to
Ricarda Steinbrecher, a molecular geneticist at the Oxford-based non-profit science watchdog group EcoNexus. Steinbrecher,
who served as a scientific expert at the hearing in Munich, notes another use of the technique on onions1 in 1987 was cited in the EPO hearing as an example that others were working on the technology.

Osterwalder notes that GM technology was much less developed then than it is now, and patents in the field were new. "Guidelines
are now better developed on whether to grant or refuse these patents," he says; a higher percentage of GM plant patents are
now refused than in the past.

Not the usual suspects

The original patent approval was opposed by a strange mix of groups, including the Canadian environmental group ETC and a
long list of big agribusiness firms involved in GM research. One of the opposing firms was Monsanto, which dropped its opposition
in 1996 after acquiring Agracetus, thus becoming owner of the patent.

Christoph Then, a GM expert at Greenpeace Germany, which cooperated with ETC in opposing the patent, was at this week's hearing
in Munich. He says representatives from the Swiss agribusiness firm Syngenta provided some of the strongest arguments against
the patent.

It is "a little strange", he admits, for Greenpeace and ETC — which are generally opposed to the use of GM soybeans — to be
arguing the same side as Syngenta, a manufacturer of GM crops. It was also unusual, adds Then, for Greenpeace to be arguing
a case that would effectively give other companies more unrestricted access to GM technologies.

Then says Greenpeace is strongly opposed to any patent that would give a company basic control over a plant species and allow
them to restrict access to technology. "For us, this patent was highly symbolic," he says.